Made by Sega Toys (oh, how far the mighty have fallen) and resembling company's Body Trainer exercise aid almost exactly, this odd little gadget measures your heart rate, providing you with helpful messages during the course of whatever undoubtedly depressing sexual episode you've decided it should be a part of. You can listen to these messages at the website (slightly NSFW, highly recommended), but here they are in convenient, easily printable list form:

The foreplay, will now begin!
Please confirm the heart rate sensor!
Your stamina will be evaluated!
The lovemaking, will now begin!
Following the beat, make love much harder!
You are making love, at a very good pace!
Making love a bit more gentler, would be perfect!
Well done! Let's make love more regularly!

The LoveTrainer will also pipe in music from your iPod for personal enjoyment, just in case you're too embarrassed to put your Star Wars Imperial March brand of doin'-it music on actual speakers. The privilege of using the LoveTrainer will set you back $80, assuming this entire site isn't some kind of elaborate hoax. [LoveTrainer—Thanks, Chris!]